<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box {
            width: 200px;
            height: 200px;
            background-color: pink;
        }
    </style>
</head>

<body>
    <div class="box"> </div>
    <script>
        var box = document.querySelector('.box');
        box.addEventListener('click', function(e) {
            var x = e.pageX - box.offsetLeft;
            var y = e.pageY - box.offsetTop;
            box.innerHTML = 'x的坐标是' + x + '，y的坐标是' + y;
        })
    </script>
</body>

</html>